L-Theanine in Matcha: What the Studies Say
L-theanine is present in green tea. Results from tablets don't automatically apply to a bowl of matcha.
By Roseline Zhou, Founder
Contents
You're wondering whether the L-theanine in matcha has an effect on stress. This amino acid is present in green tea alongside caffeine. Its presence, however, can't predict your mood, concentration, or how you'll feel after a bowl.
We discuss the two compounds together because tea contains both. In practice, the caffeine in matcha varies with the powder and the amount used. L-theanine doesn't answer a search for a caffeine-free drink.
Where is L-theanine found in green tea?
It's among the amino acids measured in tea leaves. Analyses of several teas show varying amounts among tea families, depending on the samples and their processing. Matcha comes from leaves ground into powder, but it doesn't have a universal L-theanine content.
We wouldn't infer that amount from the powder's color. Color tells you about its appearance; determining its content requires analysis. If a product gives a number, check which tea and which portion it describes.
L-theanine and stress: what can a trial tell us?
A study of an isolated compound doesn't automatically describe a bowl of matcha. In a trial with 30 adults, participants took 200 mg of L-theanine per day in tablets for four weeks. Some questionnaire scores on stress and sleep changed. Neither the dose nor the form used in that trial can predict an effect after a bowl of matcha.
We'd rather talk about the flavor and preparation we can actually judge than promise a feeling. The amount in each cup and each person's response remain unknown. If stress persists, a drink doesn't replace advice suited to your situation.
Does L-theanine cancel out caffeine?
No. The two compounds coexist in tea, but L-theanine doesn't remove caffeine. An impression of gentleness may come from the flavor, the amount used, or the time you drink it; that feeling doesn't measure a molecule's action.
We'd taste the tea with water first to learn its flavor and texture. If you always drink it with milk, keep your recipe and change just one thing at a time.
What about decaffeinated Japanese tea?
It depends on the product and the process used. The term “decaffeinated Japanese tea” doesn't, by itself, tell you how much L-theanine the product contains or whether its other compounds were preserved.